<template>
  <el-container class="home-container">
    <!-- 头部区 -->
    <el-header>
      <div>
        <img src="" alt="" />
        <span>电商后台管理系统</span>
      </div>
      <el-button type="info" @click="logout">退出</el-button>
    </el-header>
    <!-- 页面主题区域 -->
    <el-container>
      <!-- 侧边栏 -->
      <el-aside :width="isCollapse ? '64px' : '200px'">

        <!-- 关闭/展开侧边栏 -->
        <div class="toggle-button" @click="toggleCollapse">|||</div>
        <!-- 侧边栏菜单区 -->
        <el-menu
          background-color="#333744"
          text-color="#fff"
          active-text-color="#409EFF"
          :unique-opened="true"
          :collapse="isCollapse"
          :collapse-transition="false"
          :router="true"
          :default-active="activePath"
        >
        <!-- router=true开启路由模式，实现侧边栏点击某一模块跳转到：index所指定的相应模块 -->
          <!-- 一级菜单 -->
          <el-submenu :index="item.id+''" v-for="item in menulist" :key="item.id">
            <!-- 一级菜单的模板区域 -->
            <template #title>
              <!-- 图标 -->
              <i :class="iconsObj[item.id]"></i>
              <!-- 文本 -->
              <span>{{item.authName}}</span>
            </template>
            <!-- 二级菜单 -->
            <el-menu-item :index="'/' + subItem.path" v-for="subItem in item.children" :key="subItem.id"
            @click="saveNavState('/' + subItem.path)">
              <template #title>
                <!-- 图标 -->
                <i class="el-icon-menu"></i>
                <!-- 文本 -->
                <span>{{subItem.authName}}</span>
              </template>
            </el-menu-item>
          </el-submenu>
        </el-menu>
      </el-aside>

      <!-- 右侧内容主题 -->
      <el-main>
        <!-- 路由占位符 ,负责展示welcome页面-->
        <router-view></router-view>
      </el-main>
    </el-container>
  </el-container>
</template>

<script>
export default {
  data(){
    return {
      // 左侧菜单数据
      menulist: [],
      iconsObj:{
        '125': 'el-icon-user-solid',
        '103': 'el-icon-lock',
        '101': 'el-icon-s-goods',
        '102': 'el-icon-s-order',
        '145': 'el-icon-s-data',
      },
      // 是否折叠
      isCollapse: false,
      //被激活的链接地址
      activePath: '',
    }
  },
  //生命周期函数，组件一创建就会执行的函数
  created(){
    this.getMenuList();
    this.activePath=window.sessionStorage.getItem('activePath');
  },
  methods: {
    logout() {
      window.sessionStorage.clear();
      this.$router.push("/login");
    },

    // 获取所有菜单
    async getMenuList(){
      const {data: res} = await this.$http.get('menus');
      if(res.meta.status !== 200){
        return this.$message.error(res.meta.msg);
      }
      this.menulist=res.data;
      console.log(res);
    },
    // 点击按钮，切换菜单的折叠与展开
    toggleCollapse() {
      this.isCollapse = ! this.isCollapse;
    },
    //保存链接的激活状态
    saveNavState(activePath){
      window.sessionStorage.setItem('activePath',activePath);
      this.activePath=activePath;
    }
  },
};
</script>

<style lang="less" scoped>
.home-container {
  height: 100%;
}

.el-header {
  background-color: #373d41;
  // 弹性布局
  display: flex;
  // 设置内容左右贴边对齐
  justify-content: space-between;
  // 左边距为0
  padding-left: 0;
  // 退出贴边按钮居中
  align-items: center;
  // 设置文本”电商管理系统“为白色
  color: #fff;
  font-size: 20px;
  // 使文本贴边纵向居中
  > div {
    display: flex;
    align-items: center;
    span {
      // 文本间距
      margin-left: 15px;
    }
  }
}

.el-aside {
  background-color: #333744;
  .el-menu{
    border-right: none;
  }
}

.el-main {
  background-color: #eaedf1;
}
// 图标与文本间隔
.iconfont{
  margin-right: 10px;
}

.toggle-button{
  background-color: #4A5064;
  font-size: 10px;
  line-height: 24px;
  color: #fff;
  text-align: center;
  letter-spacing: 0.2em;
  cursor: pointer;
}
</style>
